I will discuss the role of model/data comparisons for past climate
changes and use of such comparisons for enhancing credibility in future
projections. I outline a framework in which data synthesis combined with
suitable modelling targets should be able to reduce uncertainty in both.
By focusing on areas that the Intergovernmental Panel on Climate Change
assessment report (IPCC AR4) highlighted as being particularly uncertain
in future projections, or where current models produce a very wide range
of responses, the relevance of paleo-climate data could be greatly
enhanced. Specific targets include: the long-term behaviour of El Nino
events and the potential response to volcanic and solar forcing; the
variability of sub-tropical rainfall and the extent of the Hadley
Circulation and their response to orbital and high-latitude forcing; ice
sheet responses on sub-millennial timescales; multi-decadal changes in
the North Atlantic ocean circulation and, certainly, overall climate
sensitivity. In each case, I will highlight data synthesis steps and
modelling approaches necessary for reducing the uncertainty.
Schmidt, G.A, 2010: Enhancing the relevance of palaeoclimate model/data
comparisons for assessments of future climate change. J. Quaternary
Sci., 25, 79-87, doi:10.1002/jqs.1314.